2. Place the track sets next to the pistons and ensure that the pistons and rings associated with each cylinder are kept in the set until the end of assembly.
3. Insert the top ring into cylinder No. 1 and push it into the cylinder with the piston bottom until the ring is at BDC (figure 23.3).
4. Measure the gap in the ring lock. by selecting a feeler gauge of the required thickness, which enters the gap with some friction (see Figure 23.4). Compare the obtained result with Technical data at the beginning of the chapter. If the gap is smaller or larger than the permissible value, measure it again to be sure.
5. If the gap is too small, it can be filed down. However, the ability to correct the gap in this way depends on the material the ring is made of and what it is coated with. Please read the instructions included with your ring set carefully.
6. A large gap is not as dangerous as a small one, unless, of course, it exceeds the maximum permissible value. To be sure, double-check the gap to ensure that you have purchased the correct size rings. If you still think it is necessary to correct the gap with a file, then clamp the file in a vice (and not a ring) in a vertical position, lubricate the top of the vice jaws, place the ring lock on the file and slide the rings back and forth across the file, pressing the ring against the vice. After filing the ring a little, check the gap again and, if necessary, file it further. Once the gap is within tolerance, use a file to remove any burrs that formed during filing.
7. Repeat this procedure for all rings of the first cylinder, and then for the remaining cylinders. During and after checking, do not mix up the rings - they must be subsequently inserted into the cylinder in which they were checked.
8. After checking and adjusting the clearances, the rings can be inserted into the piston grooves.
9. The lower one is installed first (oil scraper) ring. It consists of three parts. Insert the expander into the lower groove of the piston (figure 23.9,a). If the expander has a locking tab, it should fit into the hole in the piston groove. Then insert the lower ring collar. Do not use a ring installer for this purpose - the race can easily be damaged in the process. Instead, insert one end of the ring into the gap between the expander and the groove wall and press it against the piston. Run your finger along the ring around the piston, fitting the ring into the groove (fig. 23.9,b). Insert the top ring collar in the same way.
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10. After installing all three ring parts, make sure that the races rotate freely in the groove.
11. Next, install the second (middle) ring. It usually has a marking that should face up.
Note: Follow the instructions printed on the ring set packaging - rings from different manufacturers may require different approaches. Do not confuse the middle and top rings - they have different cross-sections.
12. To install the second ring, it is better to use a device. Make sure the ring is facing up and insert it into the middle groove (figure 23.12). Do not spread the ring more than necessary to allow it to pass through the piston.
13. Install the top ring in the same way. Remember that the markings must face up. Don't mix up the rings.
14. Install the rings on the remaining pistons in the same manner.